Process of electrolysis and apparatus therefor.



K. S. GUITEHMAN PROCESS OF ELiZGTROLYSIS ANS Aumuus $14.13;; cm.

APPLIOATKON FILED N0 11, 1912,

Patented May .21, 39 a3.

INVENTOR W WITNESSES ZMZ *2 Z ATTORNEYS K. S. GUITERMAN. PROCESS OFELEGTROLYSIS AND A'PPARATUS THEREFOR.

APPLICATION FILED NOV.11, 1912.

Patented May 27, 1913.

2 SHEBTHHEBT 2.

INVENTOR WITNESSES ATTORNEYS pul UNITED STATES KENNETH s ourrnamm, orNEW Yoax, n. Y.

rn'ocnss or ELECTROLYSIS Aim nrmrus 'rnmmroa Specification of LettersPatent.

Patented May 27', 1913.

Applicatiomflled November 11,1919. Serial 730,598.

To wl'l whom it may concern:

Be it known that I, KENNETH S. GUITEB- MAN, a citizen of the UnitedStates, residing at No. 465 West End avenue, in the borough of Manhattanof the city of New York and State of New York, have invented certain newand useful Improvements in Processes of Electrolysis and ApparatusTheretor, of which the following is a specification.

My invention relates to an improved processof electrolysis and relatesparticularly to a process in which; high current densities may beemployed.

Heretofore the desirability of maintaining a constant agitation of theelectrolyte in the presence of high current densities has beenrecognized, but in practice the necessary circulation has beenimpractical, because by so doing the anodeslimes were kept in suspensionandmechan-ically contaminated the cathode deposit. If, on the otherhand, high current densities were employed without circulation, then thecathode deposits became very uneven and developed so-called sprout-s,which not only produced. short circuits, but also collected much slimeand: impurities,

One of the primary objects of this invention is to maintain constantagitation of the electrolyte while using a hi hcurrent density andwithout contaminatlon of the cathode deposit.

A further object of the invention is to efiect removal of the anodeslimes while maintaining a practically continuous agitation of theelectrolyte in the electrolytic vat, thus avoiding the contamination ofthe oathode deposit.

Another objegt of the invention is to provide an improved form ofapparatus for carrying out the said process.

The various other objects of the invention will be more fully set forthin the accompanying description of my improved proc ess and one form ofapparatus adapted for use in carrying out the same.

In the accompanying drawings :Figure 1 is a diagrammatic plan view of anapparatus for carrying out my improved process. Fig. 2 is an endelevation in section of the electrolytic vat. Fig. 3 is a side elevationof the vat, partly in section, showing the arrangement of the electrodesand the feed In carrying out my improved process, the terminal plates orelectrodes are arranged parallel to each other in a suitable retainingvessel or a va't with an inlettor a continuous-su'pply of electrolytebetween the members ofeach pair of electrodes. The electrolyte flows i-n-apractically continuous streanifrom the inlets and passes between andin contact with the electrodes, so that the'enti-re surface 04! eachelectrode is washed and thereby scoured oi? 'slimes by the flowingstream. The velocity of the streammay be controll'ed in any desiredmanner and is always 'sufiicient to prevent the deposition of suspendedslime. Preferably, the direction 01: flow is substantially downward andtransverse to the faces of the electrodes. It is not essential howevertlfiat the supply of electrolyte should he directed initially in anapproximately horizontal path, since sub stamtia l'ly the same resultscan be accomplished by spraying or otherwise feeding the electrolyte sothat it will flow vertically across the-facesof the plates.

After passingthe electrodes, aportion of the electrolyte is continuouslywithdrawn from the vat or other retaining'vessel. Preferably, the outletis located at a i-nt below the bottoms of the electrodes, so t atthefl'ow of electrolyte with respect to the electrodes with be inapproximately the same path as the naturally falling slimes. Thatportion of the electrolyte which has been removed from the vat is thencleansed from anode slimcs;- This may be accomplished in any desiredmanner, for example, by causin the electrolyte to pass through a vacuumfilter, which may be connected with a tank incommunication with avacuumpump, so that a practically continuous supply may be maintained in saidtank. The cleansed electrol' ytewhich has been freed from anode slimesby the filter or other means is then returned to the vat th-rough'theinlets, as herei-n'hefore described.

In the particular apparatus shown in the accompanying drawings, the vata may be of rectangular sections and is provided with a hopper bottom 6having-an outlet 0 at its lowest point.- Electrodes d are suspended inthe upper portion of the vat by bus-bars e in the usual' manner. Supplypipes f are preferably supported upon the upper part of the vat, whichhave" a lujrality of feeder pipes g communicating heneath. The outletends of said feed pipes are arranged between the pairs of electrodes ina preferably horizontal plane. The outlet pipe it com municates with asuitable filter 2' that may be connected with one or more receivingtanks j that are connected with a vacuum pump is. The receiving tanksare also connected with a suitable pump, preferably a centrifugal pump1, which in turn may be connected with the inlet pipes, either directlyor through a suitable storage reservoir m. The flow of the electrolytethrough the various parts of the apparatus may be controlled as desiredby the valves n.

In operation, a continuous circulation of the electrolyte is kept up bythe several pumps which draw the'electrolyte from the vat, through thefilter into the receiving tanks, and thence it is forced into thereservoir m which may be elevated to supply to feed pipes under pressureof gravity or it is forced under pressure by the pump l directly intothe separate feed pipes which direct the electrolyte in streams betweeneach pair of electrodes.

By means of my improved process, a high rate of circulation isconstantly maintained between the electrodes where it is required, sothat concentration of the electrolyte at the cathode surface may bemaintained at a constant, thereby preventing impoverishment no matterhow great the current density, and also permitting extremely high cur-.rent densities to be employed without mechanical contamination of thecathodes. The slime is removed practically as fast as it is formed, notonly on account of the shape of .the vet, but also on account of theflow of the electrolyte, which prevents the slime from settling on thecathode and accelerates' its movement in a substantially verticalplane-downward, which is its natural falling direction. Since the slimesare removed, a smooth dense cathode deposit is attained, resulting fromthe constantly maintained concentration of the electrolyte at thecathode andfrom the washing and scouring action of the flowingelectrolyte on the cathode faces. Furthermore, the elimination of shortcircuits resulting from'slime accumulation or the formation of trees orsprouts, together with a decrease of polarization as a result of theincreased circulation,

and less temperature drop in the electrolyte, effect a considerablesaving in power. By

:my improved process also, the most impure and" slime forming materialmay be rapidly I treated and there is a great increase in the capacityofa planthaving a given surface 5 area, together with increased facilityIn handling, since the slime is removed practically continuously and itis unnecessary to permit the slime to settle in and to drain the samefrom the electrolyzin vat.

Although I have descri ed the various steps in my improved process, itis obvious that various departures therefrom within the knowledge ofthose .skilled in the art may be made without departing from the spiritof the invention, provided the means set forth in the following claimsbe employed. It is also obvious that numerous modifications may be madein the particular form of apparatus herein shown and described, whichchanges and modifications are within the scope of the invention.

I claim as my invention 1. The process of electrolysis which consists inarranging the electrodes in pairs, washing the slime from the electrodesas formed into a body of bath below the electrodes, keeping the slimesin suspension out of contact with the electrodes and causing the same toaccumulate at a predetermined point, and then continuously removing saidslimes with a portion of the bath.

2. The rocess of electrolysis which consists in subjecting each pair ofelectrodes to a continuous current of electrolyte, providing a body ofelectrolyte below the electrodes, producing currents having a definitedirectional flow througp said bath to accelerate the normal fall 0 theslimes and prevent same from coming into contact with the electrodes,collecting the slimes at a point remote from the electrodes, removingthe slimes with a portion of the electrolyte. separating'the slimes fromsaid removed portion of the electrolyte, and then returning saidelectrolyte to the bath.

3. A process of electrolysis which consists in washing the slime fromthe electrodes, causing a current of electrolyte having a definitedirectional velocity between each pair of electrodes to wash the slimefrom the surface of the el ctrodes and hold the slime out of contact terewith, maintaining said current in a direction awa from the electrodesto collect the suspen d slime, removing the slimes and a portion of theelect-rolyte, separating the slimes from said removed portion oftheelectrolyte and then returning the electrolyte to the bath.

4. A process of electrolysis which consists in causing a current ofelectrolyte between each pair of electrodes, directing each of saidcurrents in a downward direction at sub stantially uniform velocity tocarry the slimes out of contact with the electrodes, then graduallydirecting said currents toward an outlet relatively remote from theelectrodes, removing the slimes and a portion of the electrolyte throu hsaid outlet, filtering said portion of the e ectrolyte to separate thesuspended slimes and then returning said portion of the electrolytetothe bath.

5. A process of electrolysis which consists in causing a current ofelectrolyte between each pair of electrodes having suflicient velocityto wash the slimesfrom the surface of the electrodes and prevent eddycurrents, keeping the slimesin suspension out of contact with theelectrodes, causing the slimes to accumulate at a predetermined pointrelatively remote from the electrodes, and then removing said slimes anda portion of the electrolyte, separating the slimes from the electrolyteand then returning said electrolyt to the bath.

(3. A process of electrolysis which consists in washing the slimes fromthe electrodes as formed into a body of bath below the electrodes,producing currents having a definite directional flow through said bathto accelerate the normal fall of the slimes and prevent contamination ofthe electrodes, directing said currents toward an outlet relativelyremote from the electrodes, removing the slimes with a portion of theelectrolyte, separating the slimes from said electrolyte and thenreturning the electrolyte to the bath.

7. A process of electrolysis with high current densities which consistsin arranging the electrodes in pairs opposite each other, continuouslyscouring the faces of each pair of electrodes with a current of filteredelectrolyte. washing the slimes as formed into abody of bath below theelectrodes, maintaining currents having a definite directional velocityin said bath, directing said currents away from said electrodes towardan outlet relatively remote from the electrodes, continuously removingsaid slimes and a portion of the electrolyte through said outlet,separating the slimes from said removed portion of the electrolyte andreturning said electrolyte to the bath.

8. In an electrolytic apparatus, the combination with a rectangularsettling vat having a sloping bottom converging toward an outletopening, of a plurality of electrodes supported in the upper portion ofsaid vat arranged in pairs with their faces parallel to each other, afilter communicating with said outlet, and an inlet pipe communicatingwith the vat and comprising a plurality of feed pipes, one of said feedpipes being placed between each pair of electrodes and adapted to directa current between the same with a definite directional velocity towardthe outlet.

9. In an electrolytic apparatus, the combination with a rectangularsettling vat having a sloping bottom converging toward a central outletopening of a plurality of electrodes supported in the upper portion ofsaid vat arranged in pairs with their faces parallel to each other, afilter communicating with said outlet, a supply tank communicating withthe filter, and an inlet pipe communicating with the supply tank and vatand comprising a plurality of feed pipes, one of said feed pipes beingplaced between each pair of electrodes and means for forcing electrolytethrough said feed pipes with a definite directional flow toward theoutlet.

This specification signed and witnessed this 9th day of November, A. D.1912.-

KENNETH S. GUITERMAN.

Signed in the presence of M. P. VVINNE, MABEL J. COOPER.

